And I’m still getting garbage. On Export I get boxes in random places (similar to the link) and sometimes I can’t get anything to show up. I’m not sure if this is on Inkscape or ESTLcam, but considering I paid for ESTLcam that part isn’t changing.

Admittedly, I haven’t spent a lot of time working with Inkscape, but everything I’ve done has been a chore. Is it worth learning? I’ve used Tinkercad to create SVGs but it lacks text fonts and other features. Does anyone use anything else?

It sounds like you are exporting background boxes and stuff in inkscape. It isn’t estlcam adding them. Change your background in inkscape to a different color or the checkerboard, willing to bet you have a bunch of random stuff floating around.

You should look into a CAD program, fusion 360, tinkercad, sketchup. you can do Sketches in them and don’t just have to make solid objects.